Incandescent-lamp base



-(No Model.)

W- 0. BRYANT.

INGANDESOENT LAMP BASE.

Patented Apr. 9, 1895.

FIG. '5;

W/TNE SSE S:

UNITED STATES- PATENT OFFICE.

wAILDo QBRYANT, OF BRIDGEPORT, CONNECTICUT.

INCAN DESC ENT-LAM P BASE.

SPECIFICATION forming part of Letters Patent N0. 537,27], dated April 9, 1895. Application filed December 20, 1894. Serial No. 532,513. (No model.) 7

To aZZ whom it may concern.-

Be it known that I, WALDO O. BRYANT, a citizen of the United States, and a resident of Bridgeport, Fairfield county, Connecticut, have invented an Improved Incandescent- Lamp Base, of which the following is a specification.

The main object of my invention is to construct economically a strong and incombustible base for an incandescent lamp of the Thomson-Houston type.

In the accompanying drawings, Figure 1 is V a perspective view illustrating, detached from each other, parts of an incandescent lamp base constructed according to my invention. Fig. 2 is a plan view, and Fig. 3 is an inverted plan viewof the incombustible insulating disk, which I employ in carrying out my invention. Fig. 4 isa sectional view of the insulating base on the line 4-4=, Fig. 2, showing the terminals in place but not secured; and Fig. 5 is a sectional view on the line 55, Fig. 2, showing the terminals in place, and secured together with the metal ring which completes the lamp base, and by which the base is secured to the lamp.

The bases of incandescentlamps of the Thonison-l-louston type have had their insulation heretofore made of hard fiber, plaster or a composition which would become more or less plastic under heat. The bases with hard fiber are relatively costly to make, while plaster and other composition bases are not sufficiently strong. I have devised a construction of lamp base in which the insulation is a disk of porcelain.

As will be understood by reference to the drawings, this porcelain disk D is molded to a special form to combine with the terminals to be carried by it. The disk has a central opening d of sufficient size to receive a sheet metal screw-threaded thimble E, which is provided with a bottom flange e of polygonal outline, and in the under side of the porcelain disk D there is formed a recess of corresponding outline d, Fig. 3. In the present instance the outline of the flange e, and the recess d is shown as approximately triangular with somewhat curved sides. When the screwthreaded thimble E is inserted in the opening at the bottom flange e of the thimble will lit in the corresponding recess d in the un der side of the disk, as shown in Fig. 4, while the upper'end of the thimble projects above the surface of the disk. The thimble is then secured in place by flangingthe upper end of the thimble over the edges of the opening (1, as shown at e, in Fig. 5.

A suitable channel or opening a; maybe formed in the edge of the opening (1 of the disk to carry one of the leading-in wires of the lamp into position to solder it to the thimble E, which thus constitutes the central terminal of the lamp base. The other terminal of the lamp is a ring R which is provided with a series of prongs r-three in the pres ent instance.

The porcelain base is molded with a corresponding number and arrangement of openings S through it, these openings being enlarged on the upper side of the disk to form below the surface of the disk, shoulders s, over which the ends of the prongs can be bent or flanged, as shown in Fig. 5, to secure the ring terminal R onto the under side of the-insulating disk. A hole y is formed at a suitable point in the disk for the passage of the other leading-in wire through to the ring R on the under side, where the leading-in wire is soldered or otherwise secured to the ring. I also form one or more notches m on the rim of the insulating disk so that when the sheet metal ring N completing the base of the lamp is fitted over the insulating disk and the edge of the ring turned down sufficiently over the under side of the rim of the disk (as indicated in Fig. 5) to hold the insulating disk in the ring, a portion of the latter canbe punched into the notch or notches m to lock the ring and disk together and prevent one from turning independently of the other.

I claim as my invention- 1. An incandescent-lamp. base having a porcelain disk with a central opening and a surrounding polygonal recess on one side in porcelain insulating disk provided with perforations through the disk enlarged on the name to this specification in the presence of upper side to form shoulders in combination two subscribing witnesses.

with a rin terminal havin" pron s adapted T r Y,

to pass thieugh the opening? in th e said disk ALDO BRX A} 5 and their ends flanged over said shoulders, Witnesses:

substantially as described. EDITH J. GRISWOLD,

In testimony whereof I have signed my HUBERT HOWSON. 

